Every day after the runs on the salt we pick up about 1/2 a bucket of tire
chunks,
most from the outer edge. It gets rid of extra rotating mass. The old
firestones
we use to run we also had shaved. They shake like hell when the pieces come off
sorta a balance thing.
Tire pressure is also critical as is running tubes at very high speeds. Talk to
guys like
Joe Law that has had problems and done a lot of testing.
Glen
tschoen wrote:
> I don' know about LSR tires,but the reason road racers shave tires is to
>reduce
> tread "squirm" and increase contact patch. The deeper the tread the more it
> moves around which generates heat and also reduces grip.The heat can cause
> chunking of the tread. Most of the tires are also heat cycled to improve
> longevity-maybe this is important at B'ville? On another note congrats to the
> ECTA guys who got their cars pictured in the 2000 SCTA rule book:
> Beckett,Williams, Timney,Bruch.Neat!
>
>Tim
> Schoeny
>
> John Beckett wrote:
>
> > It does for bikes, but they don't mention it for cars. Maybe there is amiss
> > print? The 1999 rule book (page 15) says: "Up to 250 MPH - Shaved narrow
> > tread Super Speedway tires". Don't know that there is such a thing. Is it
> > possible that it should read: 'Shaved narrow tread OR Super Speedway tires'?
> >
> > John Beckett, LSR #79
> >
> > ----- Original Message -----
> > From: "Jonathan Amo" <webmaster@amoproductions.com>
> > To: "John Beckett" <landspeedracer@email.msn.com>
> > Sent: Thursday, January 27, 2000 3:04 AM
> > Subject: Re: concerning tires
> >
> > > I also believe that tire shaving also makes your speed rating 1 higher for
> > > shaved tires.
> > >
> > > Jonathan Amo
> > >
> > >
> > > John Beckett wrote:
> > >
> > > > John
> > > >
> > > > I believe the reason for shaving tires is to reduce the weight and
> > therefore
> > > > the effects that centrifugal force would have on the tire at high speed
> > > > (RPM).
> > > > And half tread should work just fine.
> > > >
> > > > Rolling resistance is a whole other matter, but it can't be that much.
> > My
> > > > timeslips from Maxton and Bonneville would indicate that altitude, and
> > > > slipery salt, are bigger factors than rolling resistance.
> > > >
> > > > John Beckett, LSR #79
> > > >
> > > > ----- Original Message -----
> > > > From: "john robinson" <john@engr.wisc.edu>
> > > > To: <land-speed@autox.team.net>
> > > > Sent: Wednesday, January 26, 2000 9:09 AM
> > > > Subject: concerning tires
> > > >
> > > > > Howdy,
> > > > > A few of questions and observations:
> > > > > I'm running "H" rated street radials on my H/CC at the Salt, they have
> > an
> > > > > aggressive tread design, and one of the safety techs said that I
> > should
> > > > > shave the tread for better speed. Somewhere I read that the
> > coefficient of
> > > > > friction of the Salt is on the order of cold wet asphalt, and my
> > feelings
> > > > > were (when I purchased the tires) that the aggressive tread would help
> > in
> > > > > traction. my speeds are 130-150, (150 hope full, anyway) Any thoughts
> > > > here?
> > > > > Also, I've been reading Forbes Aird 's book "Aerodynamics" published
> > by
> > > > > HPBooks1997, he has a very good section on tires and rolling
> > resistance at
> > > > > the Salt, and it states in a passage relating to the Summers Brothers
> > > > > Goldenrod that the tires soaked up 61% of the total drag at the record
> > > > > speed, although the tire model used in the equation was based on 60
> > year
> > > > > old data... are there any newer equations available? anybody know how
> > to
> > > > > test rolling resistance? or where I can get the info to do a rolling
> > > > > resistance test?
> > > > > Another book I just picked up and although it is directed at and about
> > the
> > > > > solar vehicles built at various universities, is "The Leading Edge"
> > by
> > > > > Goro Tamai, published by Robert Bentley1999. This book is focused on
> > low
> > > > > speed aerodynamics and many of the concepts can be transferred to LSR.
> > > > > Although it does have advanced math in it, with the limited algebra I
> > > > > studied in high school, (well OK attended class and worried about
> > pimples,
> > > > > girls and cars) I am able to follow most of it....probably because I
> > read
> > > > > the Aird book first, easily understood math in it.
> > > > > Two years or so ago, Motion Software (the Desktop Dyno people) were
> > > > > developing a game/engine test software about Bonneville. It seems to
> > have
> > > > > been in development, and then it died, anybody heard of it? got any
> > > > insight
> > > > > about why the program went away? they don't seem to answer their
> > email,
> > > > > although they are still in business. I'd like to get my hands on it,
> > just
> > > > > to play with it.
> > > > > anybody got any other reading material they'd like to share?
> > > > > anyway, that's about it for now, drive careful
> > > > >
> > > > > John Robinson, Mechanician
> > > > > Mechanical Engineering University of Wisconsin
> > > > > 1513 University Ave.
> > > > > Madison, Wi. 53706
> > > > > 608-262-3606
> > > > > FAX 608-265-2316
> > > > > Current World Land Speed Record Holder
> > > > > Bonneville Salt Flats
> > > > > H/GCC 92 cu.in. 1980 Dodge Colt
> > > > > 131.333 MPH set 1995
> > > > > 136.666 MPH set 1996
> > > > >
> > > > >
> > >
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